On September 13, the New York City Board of Health is scheduled to vote on a controversial proposal that would officially define an ancient Jewish ritual practice as dangerous to an infant’s life. It would require parents to agree in writing that the ritual about to be performed on their son could lead to brain damage or even death. Virtually no other religious practice in America requires parental informed consent, experts say. This would be the first.

The city’s proposal is strongly opposed by a broad coalition of devoutly Orthodox Jews, some of whom have hinted at civil disobedience against what they see as government’s encroachment on their right to practice an essential element of their faith. Given the electoral clout of these groups, it’s possible this controversy could affect next year’s race for mayor of New York City.

All this to protect the right of a mohel, the man performing a Brit Milah, or ritual circumcision, from using his mouth to suction blood from the open wound he has just made when he removed the foreskin from the penis of an 8-day-old boy.

There’s a definite yuck factor in discussing metzitzah b’peh, a practice Jews started abandoning about 150 years ago, when medical knowledge and communal sensibilities persuaded even many revered rabbis to sanction safer alternatives to clean the wound. But those Jews who have maintained the practice do so with absolute determination.

“In those communities that regard metzitzah b’peh as essential, there is simply no way that bris milah can be performed without direct oral suction,” Rabbi David Zwiebel, executive vice president of Agudah Israel of America, the major Orthodox advocacy organization, wrote to the city’s Department of Health on July 23. “For them, any government regulation of metzitzah b’peh impinges on an essential religious practice, and thus raises the highest level of constitutional concerns.”

Constitutional concerns mean a great deal here, especially at a time when anti-circumcision fervor is spreading across Europe and finding a hospitable reception among some Americans. But that is why the modest, reasonable steps recommended by New York City’s health officials ought to be supported. They do not ban the practice of metzitzah b’peh, nor restrict its use. The parental informed consent requirement, while highly unusual, points to a necessary truth: that the government’s responsibility to protect the lives of its most innocent citizens trumps all. As it should in Jewish life, too.

This is not a new controversy, but it was newly ignited by the case of a New York City infant whose death in 2011 was attributed to metzitzah p’eh.

Even though the science here is straight-forward, supporters of the practice argue that it is not. And that alone is distressing.

As the Center for Disease Control reported in June: “Oral contact with a newborn’s open wound risks transmission of HSV and other pathogens.” HSV stands for herpes simplex virus, commonly expressed by cold sores; if a newborn is infected with HSV, it can result in death or permanent disability. The CDC reports that male infants circumcised with confirmed or probable oral suction are at 3.4 times greater risk for infection than those whose Brit Milah was performed using the safer method of drawing blood and cleaning the wound through a small tube or pipette — a method that many rabbis, even among the ultra-Orthodox, have said is consistent with Jewish law.

Supporters of metzitzah b’peh are not convinced by this data. They insist that the city’s own records showing that 11 infants were infected with herpes between 2004 and 2011 by this practice (two of whom died) are based on circumstantial evidence and not indicative of a broader risk.

There’s no polite way to say this: They are wrong.“In public health, there are always ways to create doubt,” said Jay Varma, the Department of Health’s deputy commissioner for disease control, in an interview with the Forward. “But even if you have some doubts on the strength of the evidence, it is incumbent on you to protect human life.”

Voluntary testing of those who perform oral suction is simply not practical. Scientists believe that at least 70% of adults are infected with herpes, which is easily transmitted and does not always present itself in obvious ways. The mouth, a highly unsterile environment, is a breeding ground for this and other infections.

“This practice greatly increases the risk that a child will become infected with a potentially deadly infection,” Varma said. “Parents should be informed of that risk.”

Yes, parents should be informed — even at the cost of relinquishing what we like to believe is our virtually unfettered freedom to practice religion without government interference. Because the government has the right, indeed the obligation, to step in more forcefully when children are involved. Citing case law regarding such conflicts with other religions, Sarah Barringer Gordon, a highly regarded law professor at the University of Pennsylvania, told the Forward: “Where medicine and religion conflict, the concern is to protect the children.”

And the current protocols in New York State are not sufficient. After an infant death in 2005, state health officials worked with the ultra-Orthodox community to establish voluntary guidelines, with health information distributed to new mothers after they give birth in the hospital. That has not prevented infants from becoming infected or, in the instance mentioned above, from death. The more stringent parental consent form is necessary.

It’s clear that this controversy is more than a public health dispute. It is about the autonomy of religious leadership and the imperative of maintaining tradition. It is also reflects deep anxieties about the broader circumcision debate — a worry that allowing government officials to have a say over one religious practice would open the door to more robust interference.

In fact, it may have the opposite effect. “Making metzitzah b’peh about the fight about circumcision has implications for the entire Jewish community,” Marc Stern, general counsel of the American Jewish Committee, told the Forward.

In Europe, where fervent secularists are pushing governments to ban circumcision, where a German rabbi was criminally charged for doing what Jews have done for centuries, the argument is about the pain and disfigurement experienced by the infant boy. It’s an argument that is easily refuted, by weighing those real consequences with, in our mind, the far more important value of maintaining a singular religious tradition, one that actually has serious health benefits to the infant.

But if metzitzah b’peh is inextricably linked to Brit Milah and has been proven to be potentially dangerous to the infant, then opponents of circumcision have a far more potent argument in their arsenal.

New York City officials seem to have developed a reasonable compromise that protects the religious rights of parents while ensuring that they receive the information they need to make a responsible choice for their child. Our tradition must be able to absorb and adjust to new scientific understandings. Surely the rabbis whose word is law in these communities want what is best for their children, too.